The present invention relates to lighting louvers and processes for making such louvers.
There are many forms of lighting louvers, manufactured using various methods, for visually hiding light sources such as elongated fluorescent bulbs and for evenly dispersing light over a given area by reflecting light from the source from parabolic reflective surfaces. Some louvers are made of polymers that are injection molded into grid or other forms. Molds for such louvers are very expensive and do not allow for much variance in design for the resulting louver grids. Other louvers are formed of metal such as specular aluminum in individual louver sections that may be fitted together to form a complete lighting panel. This adds significant capability for the lighting designer to alter the appearance and effect of the finished panels, since the sections may be assembled in a variety of ways. Still, the manufacturing process is fairly complex and generally requires sophisticated formation and assembly machinery. This has been due at least in part to the nature of the folded type louver.
In the past, the louver shape has been stamped or otherwise cut from sheet stock, then bent into the desired configuration about numerous fold lines to arrive at the final shape for assembly with other louver sections. The material must be precisely bent about the fold lines for the final shape of the louver to be acceptable. If the folds are not precisely made, the resulting louver may not be of an acceptable shape to be used in a panel.
The drawings exemplify a prior art louver in FIGS. 1 and 2 that is formed about two fold lines at a top portion of the louver. FIG. 2 indicates the location of the two fold lines by dashed lines. If the bending procedure is not precise along both fold lines, the resulting louver shape may result in uneven or misaligned bottom marginal edges (the arcuate outer edges in FIG. 2).
Uneven edges at the bottom or outward edges of the louver are unsightly and can result in undesired specular inefficiency of the louver by reflecting light in undesired directions. It is also typical that the top or inside portions are slotted. Open slots result in inefficiency because light captured within the louver body cannot escape.
It is therefor desirable to simplify louver construction to enable use of simple machinery and to better assure a more consistent and acceptable finished louver.
It is also desirable to obtain a louver with a top or wide end portion that is closed in order to maximize specular efficiency by avoiding trapping of light within the louver interior.
A need also exists for a louver that may be formed with top or wide end surfaces that are recessed between louver ends to enable mounting of the louver in close proximity to a light source such as fluorescent lighting tubes.
The present louver, as will be understood from the following description, provides solutions to the above problems and fulfills the above noted needs.